Portable power-driven screw driver



March 18, 1941.

R. E. KELLOGG PORTABLE POWER-DRIVEN SCREW DRIVER 2 Sheets-Sheet l Filed June 2, 1939 a Q 1 4 1 H 1 m 2 Q wm i z 1 W i 6. fl WW w w M z awwmto'a 1?. E. Kelloy mm v mannin HHHHHMH Mommy.

March 18, 1941. R. E. KELLOGG PORTABLE POWER-DRIVEN SCREW DRIVER Filed June 2, 1939 2 Sheets-Sheet 2 Patented Mar. 18, 1941 UNITED STA-"res I I -,2,z3s,374l

PATENT o FIca roairanm POWER-DRIYEN scaaw nmvaa Bay E. Kellogg, Lakewood, N. Y. Application June 2, 1939, Serial No. 277,077

9 Claims. (cl. 144-32) A further object of the invention is to Drovide a screw driver including a driving element" and'a driven element, one of which is free .to

rotate on a tubular bit-receiving member and the other movable therewith, the parts beingso arranged that, when pressure is exerted on the bit, motion will be transmitted from the driving element to the d riven element to eflect' driving of a screw into the work.

A further object is to provide means for regulating the depth of penetration of the screw into the work and means for relieving pressure on the lit and automatically disconnecting the driving element from the driven element after said screw has penetrated the work to the desired depth. r

A still further object of the invention is genenally to improve this class of devices so as to increase their utility, durability and efllciency as well as to reduce the cost of manufacture.

In the accompanying drawings forming a part of this specification and in which similar numera-ls of reference indicate corresponding parts. in all the figures of the drawings- Figure 1 is a side elevation of a power-driven screw driver embodying the present invention,

Figure 2 is an enlarged longitudinal sectional view showing a screw partially driven into the work,

Figure 3 is a similar view showing thescrew driven home and the adjusting nuts in engagement with the work to relieve pressure on the driving bit, I Figure 41s a side elevation, partly in section,

45 showing the tubular member and its associated parts separated and in position to be assembled, Figure 5 isa transverse sectional view taken on the line 8-5 of Figure 2,

- Figure 6 is a longitudinal sectional view illus- BO'trating a modified form of the invention, and Figure 7 is a transverse sectional view-taken on the line '|--lof Figure 6. r

The improved device forming the subjectmatter of the present invention may be used in on connection with any type of power unit, and by way of illustration is shown applied to a portable electrically'driven power unit, in which 5 dealsnates the casing or body .portion, 8 the hand grip and 'l the chuck. The device comprises adriving member or disk] having a hollow hub portion 9 terminating in a reduced cylindrical extension iliTadapted to fit within the chuck I and to be gripped thereby so that, when current is applied to the power unit, motion will'be transmitted from said .power unit to the driving ele- 1o ment. Fittingloosely within the hub 8 of the driving element is a tubular member or sleeve H,

the walls of which are provided with registering longitudinal slots I2 and internal threads ii for engagement with a correspondingly threaded ll screw II. The head 15 of the screw ll engages a counter-sunk seat l6 formed in the inner end I of the extension it so as to permit free rotation of the driving member Q on said tubular member. Coacting with the 'a driving member Q is a driven member II also preferably in the form of a disk, and interposed between the confronting faces of the driven and driving members is a friction element l8 preferably in the form of a flat disk or washer formed of rubber, leather. or other suitable material. The driven member II- is also provided with a hub portion I! having transversely alined notches or seats 20 formed therein, and fitted in said seats is a key 2i which extends transversely through the slots "and causes the driven member to turnwith the tubular member or sleeve II. The bore of the tubular member II at the free end thereof is preferably angular in cross section, as indicated at 22, and axially slidable in said bore is a. correspondingly angularshaped driving bit 23, the free end of which normally projects beyond the adjacent end of the tubular member and is provided with one or more flns or flanges 2! for engagement with correspondingly shaped grooves 40 formed in the head of a screw, indicated at 25. It will thus be seen that the bit 23 is both nonrotatably and 'slidabiy mounted in the tubular member or sleeve. The rear end of the bit it normally bears against the adjacent edge of the ky 2| so that, .when pressure is applied to. the bit am the act of driving a screw into the work, said pressure will be transmitted to the key 2| and thence to. the driven member l'l, thereby causing said member II to frictionally engage the driving element 8 through the medium ofthe intermediate disk I! and transmit motion from the drivingelement to the driven element to rotate the bitand cause the screw 25 to penetrate the work. The exterior walls of 5 21 and 28.

the tubular member II at the free end thereof are threaded at 2C for engagement with correspondingly threaded adjusting sleeves or collars The purpose or the adjusting sleeveor collar 21 is to engage the work after the screw has penetrated said work to the desired depth and thereby relieve pressure on the bit 23 so as to disengage the driving element from the driven element and automatically stop further rotation of said bit. By adjusting the collar 21. longitudinally of the tubular member II, the depth or penetration of the screw into the work may be varied at will and after the desired adjustment of the collar 21 hasbeen effected, said collar is locked in adjusted position by movingthe collar 28 in engagement therewith. As the driving and driven members 8 and II, respectively, do

not interengage until pressure is exerted on the bit 23, the driving member is normally i'ree to revolve on the sleeve ll without rotating said sleeve and, consequently, the bit 23' maybe inserted within or removed from its seat in the tubular member without stopping the power unit.

In operation, the reduced end ll of the drivihg member I is inserted into the chuck I 01' the power unit, after which the driving bit 23 is fitted to its seat with the active end of the bit engaging the screw to be driven. As pressure is applied to the bit 22, the rear end or the bit by engagement with the key 2| will force the driven member into engagement with the driving memher and thus rotate the bit to eflect penetration of the screw into the wood. -As soon as the screw is driven home, the sleeve or collar 21 will bear against the adjacent surface or the work and thus relieve pressure on the bit which, in turn, disconnects the driving and driven members and automatically stops further rotation of the bit, as will be readily understood.

In Figures 6 and 7 of the drawings, there is illustrated a modified form of the invention, in

i which thetubular member or sleeve 29 is fastened to the driven element 20 by screws 3| which pass through slots, in the sleeve and eng e notches or recesses 33 in the bit 24, said bit being axially movable within the sleeve 29, as shown. In this form or the device, the hub ofthe driving element 35 is internally threaded at 36 for engagement with the correspondingly threaded shank 31 of a power unit, indicated at 30, and the end 28 of the tubular member or sleeve 29 by engagement with the work serves to take the pressure off the bit 34 after a screw has been driven into the work.

It will, 01' course, be understood that the .devices may be made in different sizes and shapes and attached to any type or power unit without departing from the spirit of the invention.

Having thus described the invention, what is claimed as new is:

1. A device or the class described comprising a driving member inactive when the screw penetrates the work to a predetermined depth.

2. A device of the class described comprising a sleeve, a driving member mounted for rotation on the sleeve, a'bit non-rotatably and-axially slidable in the sleeve for engagement with a screw, a driven member non-rotatably and axially slidable on the sleeve and operable by the bit,

.means actuated by pressure on the bit tor-transmitting motion from the driving member to the driven member, a collar addustably mounted on the sleeve and adapted to bear against the work for relieving pressure on the bitand rendering the driving member inactive when the screw penetratesthe work to a predetermined depth, and means for locking the collar in adjusted position.

3. A device of the class described comprising a sleeve, a bit non-rotatably and axially slidable in said sleeve, 9. driving member loosely mounted for rotation on the sleeve and adapted to engage a power chuck, a driven member non-rotatably and axially slidable on said sleeve and operable by the bit, a friction disk interposed between said members, a key carried by the driven member and extending through the sleeve for enwhereby-pressure exerted on the bit will cause the' driven and driving members to interengage and transmit rotary motion to the bit.

4. A device of the class described comprising a longitudinally slotted sleeve, a driving member mounted for rotation on one end of the sleeve and having means for engagement with a power chuck, a driven member non-rotatably and axially slidable on the sleeve and having seating notches formed therein, a key extending through the slot in the sleeve and seated in said notches, and a bit non-rotatahly and axially'slidable in the sleeve and bearing against the key for operating the driven member, said bit by engagement with the key serving to actuate the driving member to impart rotary motion to the bit when presable in the sleeve for operating the driven mem-, her, a collar adjustably mounted on the sleeve.

adjacent the bit, and means for holding the collar in a set position of adjustment.

6. A device of the class described comprising a sleeve having one end thereof exteriorly threaded and its other end formed with a longitudinal slot, a driving member loosely mounted on the sleeve and provided with a reduced extension for engagement with a power chuck, a pin extending through said extensionand having threaded engagement with the interior or the sleeve, a driven gagement with the adjacent end of the bit member non-rotatably and axially slidable on the sleeve, a key carried by the driven member and extending through the longitudinal slot-in the sleeve, a bit non-rotatably and axially slidable in the sleeve and bearing against the key for operating the driven member, and a collar adjustably 'mounted on the threaded portion of the sleeve.

,7. A device of the class described comprising a longitudinally slotted sleeve, 9. driving member loosely mounted for rotation on the sleeve and provided with a reduced extension for engagement with a power chuck, the end of said extension being counter-sunk, a pin having one end thereof provided with an enlarged head seated in said counter-sunk portion and its other end threaded within the sleeve, a driven member nonrotatably and axially slidable on' the sleeve, a friction disk interposed between the driving member and the driven member, a key carried by the driven member and extending through the slot in the sleeve, a bit non-rotatably and axially slidable in the sleeve and bearing against i the key for operating the driven member, a collar adjustably mounted on the sleeve adjacent the bit, and a second collar contacting with the firstmentioned collar for holding said first-mentioned collar in a set position of adjustment.

8. A device of the class described comprisinga. sleeve having one end thereof formed with a" longitudinal slot and its other endexteriorly threaded, the threaded end of the sleeve being formed with a seathaving angular walls, a driving member loosely mounted for rotation on the slotted end of the sleeve and provided with means for engagement with a power chuck, a pin extending loosely through the driving member and having threaded connection with the. interior of the sleeve, a driven member non-rotatably and axially slidable on the sleeve, a key carried by the driven member and extending transversely in the driving bit.

through the slot in the sleeve, a bit non-rotatably and axially slidable in the seat of the sleeve and having angular walls for engagement with the'angular walls of said seat, the rear end of the bit normally bearing against the key whereby when pressure is exerted on the bit the driving and driven members will interengage and trans-- .mit rotary motion to said bit.

9. A device of the class describedcomprising a sleeve having registering slots formed therein, a

driving member loosely mounted for rotation on the sleeve and having one end thereof provided with a threaded socket for engagement with a correspondingly threaded boss on a power unit, a driving bit non-rotatably and axially slidable in the sleeve and having one end thereof provided with an enlarged head fitting within the driving element and provided intermediate its ends with oppositely disposed notches, a driven element non-rotatably and axially slidable on the sleeve and operated by the bit, a friction disk interposed between the driving element and'the driven element, and threaded pins carried by the driven,

element and extending through the slots in the sleeve with their terminals seated in the notches .RVAY E. KEILOGG. 

